Construction method for girder in bridge, crane for pulling up girder, vehicle for carring girder, and girder used for the same

ABSTRACT

A construction method for a girder in a bridge which a plurality of piers are installed in an interval in a longitudinal direction of the bridge, a plurality of copings are installed on the piers, and a plurality of girders respectively installed between the piers are installed on the copings, the method comprising the steps of: installing at least one temporary girder on a front coping of the copings and a rear coping adjacent to the rear coping of the copings; installing a crane for pulling up a girder having a girder pulling up space therein guided by the temporary girder; providing with a girder by a pre-cast method so as to install a girder on the front coping and the rear coping; providing with a vehicle for carrying a girder, the vehicle being constituted so that load of a girder to the piers carried by the vehicle is distributed to the piers through the upper surface of the girders installed in advance; introducing the vehicle carrying a first girder moving along a guide of the temporary girder to a girder pulling up space of the crane; pulling up the first girder by the crane; drawing out the vehicle backward from the girder pulling up space; moving a first temporary girder of the temporary girders from a position where the first girder is to be installed to a front of the front coping of the one of the copings and installing the first temporary girder on a next front coping installed in a next front of the front coping and the front coping; and settling the first girder on the front coping and the rear coping by the crane is disclosed.

FIELD OF THE INVENTION

The present invention relates to a construction field, and more particularly, to a construction method for a girder in a bridge, a crane for pulling up a girder, a vehicle for carrying a girder, and a girder used for the same, capable of installing a girder on a pier for a bridge for building a bridge.

BACKGROUND OF THE INVENTION

In the conventional art, a construction structure is built by pouring concrete after installing a mold and reinforcements on the spot. However, the conventional method has a problem that the quality of the construction structure is greatly influenced by surrounding circumstances.

Accordingly, a pre-cast method is being actively supposed, by which members of a structure are provided in advance, and the members are an installed in the working place. The method has an advantage that the quality of the structure can be ensured regardless of the surrounding circumstances.

The method may have a problem that constructing equipment has to be additionally prepared near the working place, since each member of the structure has to be provided in advance. However, under the construction in a large scale, the construction duration and costs may be reduced by the method. Accordingly, the problem does not serve as a severe one.

In case of building a bridge, research is being actively performed, by which only piers are built according to an installation technique on the working place, and copings or girders manufactured in advance are installed.

For instance, according to a FSLM (Full Span Launching Method), all of girders for a bridge are provided in advance on a manufacturing line near the actual working place, and then sequentially undergo a temporary work at an upper side of piers, which is also referred to as a PSM (Pre-cast span method).

FIGS. 1 and 2 are schematic diagrams showing a basic concept of a construction method for a girder in a bridge according to the conventional art.

As shown in FIG. 1, a bridge is constructed by installing girders 30 on each upper surface of copings 20 installed above piers 10. As shown in FIG. 2, the girders 30 are sequentially moved to each section formed between the piers 10 and the copings 20 in a forward direction.

More concretely, the girder 30 is carried to a temporary work position by a vehicle 40 for carrying a girder, the vehicle moving on an upper surface of the installed girder 30. Then, the girder is pulled up by a crane thus to be installed at the temporary work position.

However, the conventional method has a disadvantage to be applied only to specific circumstances such as a railroad bridge, not to a general roadway bridge.

The railroad bridge has a characteristic that a secondary dead load (a load of a structure to be build on an upper surface of another bridge on a cobble road) or a live load (a load of a train) is much larger than a first dead load (a load of a bridge itself). With consideration of the specific characteristic, the railroad bridge is designed so that the piers 10 can have strength enough to resist large load exceeding the first dead load.

In order to minimize influence on structural stability, the girder 30 to be subsequently installed is carried through the installed piers 10, copings 20, and girder 30.

On the contrary, the general roadway bridge has a characteristic that the secondary dead load or the live load is smaller than the first dead load. Accordingly, the general roadway bridge is constructed so that each member can have strength enough to resist only the first dead load. As a result, a technique for building a railroad bridge need not to be applied to the general roadway bridge.

In order to apply a pre-cast method not by the building technique in the working place, to the roadway bridge, an additional means needs to be provided.

SUMMARY OF THE INVENTION

Therefore, an object of the present disclosure is to provide a construction method for a girder in a bridge capable of applying a pre-cast method even to a general roadway bridge, a crane for pulling up a girder, a temporary girder, a vehicle for carrying a girder, and a girder.

To achieve these and other advantages and in accordance with the purpose of the present disclosure, as embodied and broadly described herein, there is provided a construction method for a girder in a bridge which a plurality of piers are installed in an interval in a longitudinal direction of the bridge, a plurality of copings are installed on the piers, and a plurality of girders respectively installed between the piers are installed on the copings, the method comprising the steps of: installing at least one temporary girder on a front coping of the copings and a rear coping adjacent to the rear coping of the copings; installing a crane for pulling up a girder having a girder pulling up space therein guided by the temporary girder; manufacturing a girder by a pre-cast method so as to install a girder on the front coping and the rear coping; providing with a vehicle for carrying a girder, the vehicle being constituted so that load of a girder to the piers carried by the vehicle is distributed to the piers through the upper surface of the girders installed in advance; introducing the vehicle carrying a first girder moving along a guide of the temporary girder to a girder pulling up space of the crane; pulling up the first girder by the crane; drawing out the vehicle backward from the girder pulling up space; moving a first temporary girder of the temporary girders from a position where the first girder is to be installed to a front of the front coping of the one of the copings and installing the first temporary girder on a next front coping installed in a next front of the front coping and the front coping; and settling the first girder on the front coping and the rear coping by the crane.

The construction method for a girder in a bridge further comprises: the steps of introducing a vehicle moving by being guided by the temporary girder and the first girder and moving a second girder of the girders which is secondly installed for carrying a second girder to a girder pulling up space of the crane; pulling up the second girder by the crane; drawing out the vehicle backward from the girder pulling up space; moving a second temporary girder of the temporary girders from a position where the second girder is to be installed to a front of the front coping of the one of the copings and installing the second temporary girder on a next front coping installed in a next front of the front coping and the front coping; and settling the second girder on the front coping and the rear coping by the crane.

The construction method for a girder in a bridge further comprises a step of moving the crane guided by a guide of the first and the second temporary girders, after the step of settling the second girder.

Preferably, each of the piers may be provided with in an interval in a width direction of the bridge.

To achieve these and other advantages and in accordance with the purpose of the present disclosure, as embodied and broadly described herein, there is also provided a crane for the construction method, comprises a crane body and a plurality of supporters vertically installed at a lower side of the crane body, the supporters supporting the crane body, wherein the supporters comprise: a front left supporter and a front right supporter installed at the front coping; and a rear left supporter and a rear right supporter installed at the girder installed in advance.

The crane for pulling up a girder further comprises an up-down girder pulling device installed at the crane body, the up-down girder pulling device having a girder temporary mounting unit for pulling up a girder, in order to pull up or be settled to an upper side of a girder; and a right-left girder moving device for moving the up-down girder pulling device in right and left directions.

The crane for pulling up a girder further comprises a supplementary supporter installed at the lower side of the crane body so as to be opened and closed in up and down directions, and operated such that a lower end thereof is installed at the coping or the girder installed in advance when being closed, for resisting a load of the pulled-up girder together with the plurality of supporters when the girder is pulled up by the up-down girder pulling device.

Preferably, a crane base portion supported by being contacted with an upper surface of the coping or the girder installed in advance and a crane interval adjusting unit for adjusting an interval between the lower end of the supplementary supporter and the crane base portion may be provided with at the end of the supplementary supporter.

Preferably, the supplementary supporter is installed between the rear left supporter and the rear right supporter.

The crane for pulling up a girder further comprises: an up-down temporary girder pulling device installed at the crane body, the up-down temporary girder pulling device having a temporary girder temporary mounting unit for pulling up a temporary girder in order to pull up or be settled to an upper side of a temporary girder; and a back-forth temporary girder moving device for moving the up-down temporary girder pulling device in back and forth directions.

The crane for pulling up a girder further comprising a right-left temporary girder moving device for moving the up-down temporary girder pulling device in right and left directions.

The crane for pulling up a girder further comprises a temporary girder supporting portion vertically installed at a lower side of the crane body; and a temporary girder mounting and driving unit installed at a lower end of the temporary girder supporting portion and mounted at the temporary girder, for allowing a relative operation between the temporary girder and the lower end of the temporary girder supporting portion.

Preferably, the temporary girder mounting and driving portion may include a temporary girder mounting portion extended by being divided into two parts from the lower end of the temporary girder supporting portion; and a side guide roller portion installed at a lower end of the temporary girder mounting portion, and moving along side guide grooves formed at both sides of the temporary girder.

Preferably, the crane body may include a crane extended body portion extending towards a front of the front coping, and the temporary girder supporting portion and the temporary girder mounting and driving unit are respectively installed at sides of the front left supporter and the front right supporter, and at a front lower side of the crane extended body portion, respectively.

A pair of the temporary girder supporting portions are installed at right and left sides of the front left supporter, and a pair of the temporary girder mounting and driving units are installed at right and left sides of the front right supporter.

To achieve these and other advantages and in accordance with the purpose of the present disclosure, as embodied and broadly described herein, there is still also provided a temporary girder used to the construction method, comprises side guide grooves formed at both sides for guiding the crane.

According to a second aspect, there is provided a temporary girder used to the construction method, wherein the temporary girder is installed at right and left sides of the front left supporter in one pair, and is installed at right and left sides of the front right supporter in one pair.

According to a third aspect, there is provided a temporary girder used to the construction method, comprising: a temporary girder base portion installed at a lower side thereof, and supported by contacting an upper surface of the coping; and a temporary girder interval adjusting portion for adjusting an interval between a lower surface of the temporary girder and the temporary girder base portion.

According to a fourth aspect, there is provided a temporary girder used to the construction method comprising: a temporary girder moving base portion installed on a lower surface of the temporary girder so as to be movable back and forth, and installed on an upper surface of the front coping or the next front coping, for preventing downward deformation of the temporary girder being moved towards a front side of the front coping; and a moving base portion driving device for applying a driving force to the temporary girder moving base portion in back and forth directions.

According to a fifth aspect, there is provided a temporary girder used to the construction method comprising: a temporary girder moving base portion installed on a lower surface of the temporary girder so as to be movable back and forth, and installed on an upper surface of the front coping or the next front coping, for preventing downward deformation of the temporary girder being moved towards a front side of the front coping; a moving base portion driving device for applying a driving force to the temporary girder moving base portion in back and forth directions; and a moving base portion temporary coupling device for temporarily coupling the moving base portion to the temporary girder when the temporary girder is forward moved by the crane for pulling up a girder.

To achieve these and other advantages and in accordance with the purpose of the present disclosure, as embodied and broadly described herein, there is yet still also provided a vehicle for carrying a girder, used to the construction method comprising: a left wheel operated by a guide of the first temporary girder or the first girder; a right wheel operated by a guide of the second temporary girder or the second girder; and a central body portion having a supporting portion for the girder at a central part thereof, for connecting the left and the right wheels with each other.

According to a second aspect, there is provided a vehicle for carrying a girder, used to the construction method comprising: a left wheel operated by a guide of the first temporary girder or the first girder;

a right wheel operated by a guide of the second temporary girder or the second girder; and

a central body portion having a supporting portion for the girder at a central part thereof, for connecting the left and right wheels with each other, wherein one pair of right and left head portions are formed at a front end of the left wheel by being divided into two so as to be driven via one pair of temporary girder mounting and driving portions installed at right and left sides of the front left supporter, wherein one pair of right and left head portions are formed at a front end of the right wheel by being divided into two so as to be driven via the one pair of temporary girder mounting and driving portions installed at right and left sides of the front right supporter.

Preferably, the vehicle for carrying a girder further comprises a wheel connecting portion installed at each front end of the one pair of head portions of the left wheel and the one pair of head portions of the right wheel, for connecting the respective one pair of head portions of the left and right wheels with each other; and wheel connecting portion opening/closing means for opening and closing the wheel connecting portion, so as to prevent interference between the wheel connecting portion and the temporary girder mounting and driving portion while the wheel is driven.

Preferably, the wheel connecting portion opening/closing means may include a hinge portion installed at one end of the wheel connecting portion; and a wheel connecting portion opening/closing device mounted at the hinge portion, for opening and closing another end of the wheel connecting portion.

According to a third aspect, there is provided a vehicle for carrying a girder, used to the construction method comprising: a left wheel operated by a guide of the first temporary girder or the first girder; a right wheel operated by a guide of the second temporary girder or the second girder; and a central body portion having a supporting portion for the girder at a central part thereof, for connecting the left and right wheels with each other, wherein the supporting portion of the girder comprises: one pair of wing portions for upward supporting the girder; and a wing portion opening/closing device for inward closing the one pair of wing portions, so as to prevent interference between the one pair of wing portions and the supplementary supporter, at the time when the vehicle for carrying a girder is backward moved after the supplementary supporter is closed.

To achieve these and other advantages and in accordance with the purpose of the present disclosure, as embodied and broadly described herein, there is another yet still also provided a girder used to the construction method comprising: a guide groove formed on an upper surface of the girder, for guiding a lower end of the rear left supporter or the rear right supporter of the crane for pulling up a girder, by a guide of the first and the second temporary girders installed at upper sides of the second front coping and the front coping, at the time when the crane for pulling up a girder is moved to be installed at upper sides of the next front coping and the front coping.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 are schematic diagrams showing a construction method for a girder in a bridge according to the conventional art;

FIG. 1 is a side view; and

FIG. 2 is a perspective view;

FIGS. 3 to 10 are mimetic diagrams showing a construction method for a girder in a bridge according to the present invention;

FIG. 3 is a perspective view showing a step of installing a temporary girder;

FIG. 4 is a perspective view showing a step of installing a crane for pulling up a girder;

FIG. 5 is a perspective view showing a step of introducing a vehicle for carrying a first girder;

FIG. 6 is a perspective view showing a step of pulling up a first girder;

FIG. 7 is a perspective view showing a step of moving a temporary girder;

FIG. 8 is a perspective view showing a step of settling a first girder;

FIG. 9 is a perspective view showing a step of settling a second girder;

FIG. 10 is a perspective view showing a step of moving a crane for pulling up a girder;

FIGS. 11 to 43 are views showing each construction process according to the present invention,

FIGS. 11 to 13 are perspective views showing a step of introducing a vehicle for carrying a girder;

FIGS. 14 to 17 are perspective views showing a step of passing a wheel of the vehicle for carrying a girder;

FIGS. 18 and 19 are perspective views showing a step of closing a supplementary supporter;

FIGS. 20 and 21 are perspective views showing a step of pulling up a first girder by a crane for pulling up a girder;

FIGS. 22 to 24 are perspective views showing a step of opening and closing a wing portion of the vehicle for carrying a girder;

FIGS. 25 and 26 are perspective views showing a step of drawing out the vehicle for carrying a girder;

FIGS. 27 to 38 are perspective views showing a step of moving a temporary girder;

FIGS. 39 and 40 are perspective views showing a step of settling a first girder;

FIGS. 41 and 42 are perspective views showing a step of settling a second girder; and

FIG. 43 is a perspective view showing a step of moving a crane for pulling up a girder.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, a construction method for a girder in a bridge, a crane for pulling up a girder, a temporary girder, a vehicle for carriage a girder, and a girder used for the same will be explained in more detail with reference to the attached drawings.

FIGS. 3 to 10 are mimetic diagrams showing a construction method for a girder in a bridge according to the present invention.

As shown, in the present invention, a plurality of piers 10 are installed in an interval in a longitudinal direction of the bridge. A plurality of copings 20 are installed on the piers 10, and a plurality of girders 100 respectively installed between the piers are installed on the copings.

The construction method will be explained according to a construction order.

First, at least one temporary girder 200 on the front coping 21 of the copings 20 and the rear coping 22 of the copings 20 where the plurality of girders 100 are to be settled (a step of installing at least one temporary girder shown in FIG. 3).

Next, by a guide of the temporary girder 200, a crane 300 for pulling up a girder having a girder pulling up space 301 therein is installed on the front coping 21 and a girder 100 installed in advance (a step of installing a crane for pulling up a girder shown in FIG. 4).

Next, a girder 100 is manufactured or provided with by a pre-cast method in order to install a girder 100 on the front coping 21 and the rear coping 22 (a step of providing with a girder).

Next, a vehicle 400 for carrying a girder is provided. The vehicle 400 is being constituted so that load of a girder 100 to the piers 10 carried by the vehicle 400 is distributed to the piers 10 through the upper surface of the girders 100 installed in advance (a step of providing a vehicle for carrying a girder).

Next, the vehicle is introduced for carrying a first girder 100 a to the girder pulling space 301 of the crane 300, by moving along the guide of the temporary girder 200. (a step of introducing a vehicle for carrying a first girder shown in FIG. 5)

Next, the first girder 100 a is upwardly pulled by the crane 300 (a step of pulling up a first girder shown in FIG. 6).

Next, the vehicle 400 is backward drawn out of the girder pulling space 301 (a step of drawing out the vehicle for carrying a first girder shown in FIG. 6).

Next, a first temporary girder 200 a of the temporary girders 200 is moved from a position where the first girder 100 a is to be installed to a front of the front coping 21, and the first temporary girder 200 a on a next front coping 21 a installed in a next front of the front coping 21 and the front coping 21 is installed (a step of moving a first temporary girder shown in FIG. 7).

Next, the first girder 100 a is settled on the front coping 21 and the rear coping 22 by the crane 300 (a step of settling the first girder shown in FIG. 8).

As the above steps are repeated, a next girder is settled next the first girder, and the same steps are performed in a longitudinal direction of the bridge, thereby obtaining a bridge.

The construction method according to the present invention is differentiated from the conventional method by the following two aspects.

First, when the girders 100 are settled on the copings 20, one girder of the girders is settled in one time of the above steps.

More concretely, in case of a general roadway bridge, a plurality of girders are settled between piers and one of the plurality of girders is settled in one time of the steps, in order to overcome the conventional problem that the girder 100, the pier 10 and the copings are not installed with a high strength differently from a railroad bridge.

Second, in a process for carrying the girder 100 to be settled through an upper surface of the girder 100 installed in advance and then pulling up the girder 100 by the crane 300, a new element, temporary girder is used so as to uniformly distribute loads of the girder 100 to be installed, the crane 300, and the vehicle 400 to at least two copings 20 and the piers 10 supporting the copings 20.

That is, since the vehicle 400 is supported by the girder 100 installed in advance and the temporary girder 200, during the vehicle 400 is moved, the loads are distributed to the copings 20 and the piers 10 installed at least two interval.

Furthermore, since the crane 300 is installed on the front coping 21 and the girder 100 installed in advance, the loads thereof is distributed to the two copings 20 and the piers 10.

In the present invention, an construction method by a pre-cast having advantages such as a high quality, a shortened construction duration, and a reduced construction cost without influencing on structural stability can be applied to a general roadway bridge.

A process subsequent to the installation of the first girder 100 a will be explained in more detail.

First, the vehicle 400 is introduced for carrying a second girder 100 b to the girder pulling space 301 of the crane 300, by moving along the temporary girder 200 and the first girder 100 a installed in advance. (a step of introducing a vehicle for carrying a second girder shown in FIG. 5)

Next, the second girder 100 b is upwardly pulled by the crane 300 (a step of pulling up a second girder shown in FIG. 6).

Next, the vehicle 400 is backward drawn out of the girder pulling space 301 (a step of drawing out the vehicle for carrying a second girder shown in FIG. 6).

Next, a second temporary girder 200 b of the temporary girders 200 installed where the second girder 100 b is to be settled is moved to a front of the front coping 21, and the second girder 100 b is installed on the next front coping 21 a and the front coping 21 by the crane 300 (a step of mounting the second girder shown in FIG. 7).

The second girder 100 b is installed on the front coping 21 and the rear coping 22 (a step of installing the second girder shown in FIG. 9).

Next, the crane 300 is moved to a next position and installed on the next front coping 21 a and the front coping 21, by being guided by the first temporary girders 200 a and the second temporary girders (a step of moving a crane for pulling up a girder shown in FIG. 10).

As the above steps are repeated in a longitudinal direction of the bridge, a bridge having a desired length can be obtained.

While the crane 300 is moved, since a load of the crane 300 is uniformly distributed by the settled girder 100 and the temporary girder 200, structural stability for a bridge is not degraded at all.

The plurality of piers 10 preferably are provided with in an interval in a width direction of the bridge for structural stability. That is, the plurality of piers 10 includes a left pier 10 a and a right pier 10 b in a width direction of the bridge.

Hereinafter, a preferred embodiment of the present invention will be explained in more detail with reference to FIGS. 11 to 43.

First, a preferred embodiment of the temporary girder 200, the crane 300, the vehicle 400, each used to the construction method according to the present invention will be explained. Then, each drawing will be explained according to a process.

Hereinafter, a preferred embodiment of the crane 300 will be explained.

The crane 300 includes a crane body 310. And The crane 300 includes a plurality of supporters 320 vertically mounted at a lower side of the crane body 310 and supporting the crane body 310. Preferably, the plurality of supporters 320 include a front left supporter 321 and a front right supporter 322 installed at the front coping 21, and a rear left supporter 323 and a rear right supporter 324 installed at the settled girder 100 (supported by the rear coping 22) (refer to FIGS. 11, 12, 17, 18, 21, 26, 30, 31, 41, 43).

Here, a load of the crane 300 is distributed to the front coping 21, the rear coping 22, and the piers 10 supporting the front coping 21 and the rear coping 22. Accordingly, even when the load of the crane 300 is increased by pulling up the girder 100 to be settled, structural stability for a bridge is not degraded at all.

And, after the first girder 100 a to be settled is carried by the vehicle 400 to a girder pulling up space 301 of the crane 300, the first girder 100 a is pulled up by the crane 300. Then, the first girder 100 a is downward settled.

To this end, the crane 300 includes an up-down girder pulling device 330. The up-down girder pulling up device 330 is installed at the crane body 310 and having a girder temporary mounting unit 331 that is temporarily settled on the girder 100, in order to pull up or settling the girder 100 (refer to FIGS. 20, 21, 26 and 32)

And the crane 300 includes further a right-left girder moving device 332 for moving the up-down girder pulling device 330 in right and left directions, in order to settle the pulled-up girder 100 to be settled position (refer to FIGS. 39, 40 and 42)

The crane 300 includes further a supplementary supporter 340 for resisting a load of the pulled-up girder 100 together with the plurality of supporters 320 when the girder 100 is pulled up by the up-down girder pulling device 330.

Here, when the vehicle 400 is introduced into or drawn out of the crane 300, the vehicle 400 and the supplementary supporter 340 may interference each other (refer to FIGS. 22 to 26). However the supplementary supporter 340 is necessary when the settled girder 100 is pulled up by the crane 300 (that is, after the vehicle 400 is introduced into the crane 300). Accordingly, the supplementary supporter 340 may be provided with in order not to interfere with the vehicle 400 when performing the step of introducing the vehicle 400 for carrying a girder.

That is, the supplementary supporter 340 is installed at the lower side of the crane body 310 so as to be opened and closed in up and down directions, and is operated such that a lower end thereof is installed at the copings 20 or the girder 100 installed in advance when being closed. Also, the supplementary supporter 340 is opened when the vehicle 400 is introduced into (refer to FIGS. 11 and 12) and is closed just before the girder 100 to be settled is pulled up (refer to FIGS. 18 and 19).

Preferably, the supplementary supporter 340 includes a crane base portion 341 supported by being contacted with an upper surface of the copings 20 or the girder 100 installed in advance; and a crane interval adjusting unit 342 for adjusting an interval between the lower end of the supplementary supporter 340 and the crane base portion 341 (refer to FIG. 19). The crane base portion 341 and the crane interval adjusting unit 342 are provided with at the end of the supplementary supporter 340. Accordingly, when the supplementary supporter 340 is opened and closed, the supplementary supporter 340 is stably settled to the upper surface of the copings 20 or the girder 100 installed in advance.

The rear left supporter 323 and the rear right supporter 324 are installed on the girder 100 installed in advance (supported by the rear coping 22). The reason is why when the crane 300 is moved, the rear left and right supporters 323 and 324 have to be moved along the first girder 100 a installed in advance and a second girder 100 b.

However, in case the rear supporters 323 and 324 are supported by being contacted with an upper surface of the girder 100 installed in advance, the upper surface of the girder 100 installed in advance may be damaged by a partially concentrated stress occurred when the first girder 100 a is pulled up.

To prevent the problem, the supplementary supporter 340 is installed between the rear left supporter 323 and the rear right supporter 324, thereby uniformly distributing a load occurred when the first girder 100 a is pulled up, to the girder 100 first (Refer to FIG. 21).

And the first girder 100 a to be settled is pulled up by the up-down girder pulling device 330, and then the vehicle 400 is drawn out. Next, the first temporary girder 200 a positioned where the first girder 100 a is to be installed, is moved to a front of the front coping 21 (Refer to FIG. 7: a step of moving a first temporary girder). Accordingly to this end, the crane 300 is provided with the following construction.

The crane 300 for pulling up a girder further comprises: an up-down temporary girder pulling device 350 installed at the crane body 310, the up-down temporary girder pulling device 350 having a temporary girder temporary mounting unit 351 which is temporarily mounted at an upper side of the temporary girder 200, for upward pulling the temporary girder 200 or downward mounting the temporary girder 200; and a back-forth temporary girder moving device 352 for moving the up-down temporary girder pulling device 350 in back and forth directions (Refer to FIGS. 27, 30, 31, 36 and 37).

Under the configuration, the temporary girder 200 is temporarily mounted by the temporary girder temporary mounting unit 351, then is pulled up by the up-down temporary girder pulling device 350, and then is forward moved by the back-forth temporary girder moving device 352.

The temporary girder 200 installed of a plurality of temporary girders 200 a and 200 b is moved by at least two times, sequentially. Accordingly, the crane 300 for pulling up a girder needs not have the up-down temporary pulling device 350 and the back-forth temporary girder moving device 352 in plurality, but needs only one. Rather, the crane 300 for pulling up a girder is provided with a right-left temporary girder moving device 353 for moving the second temporary girder 200 b by moving the up-down temporary girder pulling device 350 in right and left directions.

The process for forward moving the temporary girder 200 by the back-forth temporary girder moving device 352 (refer to FIGS. 30, 31 and 32), may have a limitation due to a structure of the supporters 320 of the crane 300 for pulling up a girder (refer to FIG. 36). In this case, additional means for forward moving the temporary girder 200 is required.

After the plurality of girders 100 a and 100 b are completely installed, in a reverse manner, the process for forward moving the crane 300 for pulling up a girder (refer to FIG. 43) may be performed by the temporary girder fixed to upper sides of the second front coping 21 a and the front coping 21.

To this end, the crane 300 for pulling up a girder further comprises a temporary girder supporting portion 361 vertically installed at a lower side of the crane body 310; and a temporary girder mounting and driving unit 360 installed at a lower end of the temporary girder supporting portion 361 and mounted at the temporary girder 200, for allowing a relative operation between the temporary girder 200 and the lower end of the temporary girder supporting portion 361 (refer to FIGS. 15, 17, 36 and 37).

Preferably, the temporary girder mounting and driving unit 360 may have any structure to allow a relative operation of the temporary girder 200 between the lower end of the temporary girder supporting portion 361, and includes a temporary girder mounting portion 362 extended by being divided into two parts from the lower end of the temporary girder supporting portion 361; and a side guide roller portion 363 installed at a lower end of the temporary girder mounting portion 361, and moving along a side guide groove 210 formed at both sides of the temporary girder 200 (refer to FIGS. 15 and 36).

For stable mounting, the temporary girder 200 is preferably extended in a forward direction with a certain length via upper sides of the front coping 21 and the second front coping 21 a.

For mutual stable mounting between the temporary girder 200 and the crane 300 for pulling up a girder, the crane body 310 includes a crane extended body portion 311 extended towards a front side of the front coping 21. Also, the temporary girder supporting portion 361, and the temporary girder mounting and driving portion 360 are installed at sides of the front left supporter 321 and the front right supporter 322 and at a front lower side of the crane extended body portion 311, respectively (refer to FIGS. 30, 31, 32, 33 and 43).

In the aspect of structural stability, the plurality of temporary girders 200 are installed at right and left sides of the front supporters 321 and 322 of the crane 300 for pulling up a girder.

More concretely, one pair of the temporary girders 200 are installed at right and left sides of the front left supporter 321, and one pair of the temporary girders 200 are installed at right and left sides of the front right supporter 322 (Refer to FIGS. 30, 32 and 37).

Here, the temporary girder supporting portion 361 of the crane 300 for pulling up a girder, and the temporary girder mounting and driving portion 360 are respectively installed at right and left sides of the front left supporter 321 in one pair, and at right and left sides of the front right supporter 322 in one pair. Accordingly, the temporary girder supporting portion 361 and the temporary girder mounting and driving portion 360 are supported together with the temporary girders 200 installed in each one pair at right and left sides of the front right and left supporters 321 and 322 (Refer to FIGS. 30 and 37).

Hereinafter, a preferred embodiment of the temporary girder 200 will be explained.

The temporary girder 200 of the present invention serves to distribute a load of the vehicle 400 for carrying a girder being moved, to apply a driving force to the crane 300 for pulling up a girder so as to move the crane 300, and to distribute a load of the crane 300 for pulling up a girder.

As aforementioned, the temporary girder mounting and driving portion 360 of the crane 300 for pulling up a girder includes a temporary girder mounting portion 362 extended by being divided into two parts from the lower end of the temporary girder supporting portion 361; and a side guide roller portion 363 installed at a lower end of the temporary girder mounting portion 362, and at both sides of the temporary girder 200. Here, a side guide groove 210 for guiding the side guide roller portion 363 is formed at both sides of the temporary girder 200 (Refer to FIGS. 15 and 36).

In the aspect of structural stability, the plurality of temporary girders 200 are installed in one pair at right and left sides of the front left supporter 321 of the crane 300 for pulling up a girder, and are installed in one pair at right and left sides of the front right supporter 322 of the crane 300 for pulling up a girder (Refer to FIGS. 30, 32 and 37).

The temporary girder 200 is installed at an upper side of the coping 20. In order to control a level from the girder 100 installed in advance, a horizontal degree of the crane 300 for pulling up a girder, etc., the temporary girder 200 includes a temporary girder base portion 220 mounted at a lower side thereof, and supported by contacting an upper surface of the coping 20; and a temporary girder interval adjusting portion 221 for adjusting an interval between a lower surface of the temporary girder 200 and the temporary girder base portion 220 (refer to FIG. 28).

As aforementioned, the process for forward moving the temporary girder 200 by the back-forth temporary girder moving device 352 (FIGS. 30, 31 and 32) may have a limitation due to a structure of the supporters 320 of the crane 300 for pulling up a girder (FIG. 6). In this case, the crane 300 for pulling up a girder further comprises a temporary girder supporting portion 361 vertically installed at a lower side of the crane body 310; and a temporary girder mounting and driving portion 360 installed at a lower end of the temporary girder supporting portion 361 and mounted at the temporary girder 200, for allowing a relative operation of the temporary girder 200 with respect to the lower end of the temporary girder supporting portion 361. By the crane 300 for pulling up a girder, the temporary girder 200 can be forward moved (Refer to FIGS. 15, 17, 36 and 37).

Here, the temporary girder 200 is forward moved by being supported by the temporary girder supporting portion 361 of the crane 300 for pulling up a girder, with a state of being upward separated from the coping 20. If a fore end of the temporary girder 200 is protruding from the temporary girder supporting portion 361 by a distance more than a certain degree, the fore end of the temporary girder 200 may be downward deformed.

To solve the problem, the temporary girder 200 comprises: a temporary girder moving base portion 230 mounted on a lower surface thereof so as to be movable back and forth, and installed on an upper surface of the front coping 21 or the second front coping 21 a; and a moving base portion driving device 231 for applying a driving force to the temporary girder moving base portion 230 in back and forth directions (refer to FIGS. 33 and 34).

In this structure, the temporary girder 200 is forward moved by a certain distance by the back-forth temporary girder moving device 352, and then the temporary girder moving base portion 230 is forward moved by the moving base portion driving device 231 (refer to FIG. 33). Accordingly, the temporary girder moving base portion 230 is mounted on an upper surface of the second front coping 21 a (refer to FIG. 34). Also, the temporary girder 200 can be completely moved without downward deformation with making the temporary girder moving base portion 230 as a supporting point.

When the temporary girder 200 is moved by the back-forth temporary girder moving device 352, the temporary girder moving base portion 230 has to be also forward moved together with the temporary girder 200. To this end, the temporary girder comprises a moving base portion temporary coupling device 232 for temporarily coupling the moving base portion 230 to the temporary girder 200 when the temporary girder 200 is forward moved by the crane 300 for pulling up a girder (refer to FIGS. 29 and 32).

Under this configuration, before the temporary girder 200 is moved, the temporary girder moving base portion 230 mounted on an upper surface of the front coping 21 and serving as a supporting point, is temporarily coupled to the temporary girder 200 by the moving base portion temporary coupling device 232 (refer to FIG. 29). Next, when the temporary girder 200 is moved, the temporary girder moving base portion 230 is moved together with the temporary girder 200 (refer to FIG. 32). When moved to a certain point, the temporary girder moving base portion 230 is self-driven by the moving base portion driving device 231 itself, in a state that the temporary girder 200 is stopped (refer to FIG. 33), thereby to reach above the second front coping 21 a (refer to FIG. 34). Then, the temporary girder moving base portion 230 is separated from the temporary girder 200 by a release operation of the moving base portion temporary coupling device 232, thereby serving as a supporting point (refer to FIG. 35).

Hereinafter, a preferred embodiment of the vehicle 400 for carrying a girder will be explained.

In order to sequentially install the plurality of girders 100 a and 100 b, the plurality of temporary girders 200 a and 200 b are installed at positions where the plurality of girders 100 a and 100 b are to be installed. Then, the vehicle 400 for carrying a girder is moved via an upper side of the temporary girder 200.

The vehicle 400 for carrying a girder, used to the construction method for a girder in a bridge according to the present invention, comprises: a left wheel 410 a operated by guide of the first temporary girder 200 a or the first girder 100 a; a right wheel 410 b operated by guide of the second temporary girder 200 or the second girder 100 b; and a central body portion 430 having a supporting portion 420 of the girder at a central part, for connecting the left and right wheels 410 a and 410 b with each other (refer to FIGS. 13 and 26).

For structural stability, the plurality of temporary girders 200 are installed at right and left sides of the front left supporter 321 in one pair, and are installed at right and left sides of the front right supporter 322 in one pair (refer to FIGS. 30, 32 and 37). Here, the temporary girder supporting portion 361 and the temporary girder mounting and driving portion 360 of the crane 300 for pulling up a girder, are respectively installed at right and left sides of the front left supporter 321 in one pair, and are respectively installed at right and left sides of the front right supporter 322 in one pair, thereby to be supported together with the temporary girders 200 installed in each one pair at right and left sides of the front right and left supporters 321 and 322 (refer to FIGS. 30 and 37).

Under the configuration of the crane 300 for pulling up a girder, while the vehicle 400 for carrying a girder is forward moved, each head portion of the left wheel 410 a and the right wheel 410 b may interfere with the temporary girder mounting and driving portion 360 of the crane 300 for pulling up a girder.

To solve the problem, one pair of right and left head portions 411 a and 412 a are formed at a front end of the left wheel 410 a by being divided into two so as to be driven via the one pair of temporary girder mounting and driving portions 360 installed at right and left sides of the front left supporter 321. Also, one pair of right and left head portions 411 b and 412 b are formed at a front end of the right wheel 410 b by being divided into two so as to be driven via the one pair of temporary girder mounting and driving portions 360 installed at right and left sides of the front right supporter 322 (refer to FIGS. 14 to 17).

In order to stably move on upper surfaces of the plurality of temporary girders 200, the vehicle 400 for carrying a girder having divided head portions, preferably further comprises, a wheel connecting portion 413 formed at each front end of the one pair of head portions 411 a and 412 a of the left wheel 410 a and the one pair of head portions 411 b and 412 b of the right wheel 410 b, for connecting the respective one pair of head portions 411 a, 412 a and 411 b, 412 b of the left and right wheels 410 a and 410 b with each other (refer to FIGS. 14 and 15).

Preferably, the vehicle 400 for carrying a girder, further comprises wheel connecting portion opening/closing means 440 for opening and closing the wheel connecting portion 413, so as to prevent interference between the wheel connecting portion 413 and the temporary girder mounting and driving portion 360 while the wheel 410 is driven (refer to FIGS. 14 and 15).

Preferably, any type of the wheel connecting portion opening/closing means 440 for opening and closing the wheel connecting portion 413 may be used. The wheel connecting portion opening/closing means 440 includes a hinge portion 441 installed at one end of the wheel connecting portion 413; and a wheel connecting portion opening/closing device 442 mounted at the hinge portion 441, for opening and closing another end of the wheel connecting portion 413 (refer to FIG. 14).

As aforementioned, the supplementary supporter 340 of the crane 300 for pulling up a girder, is installed at a lower side of the crane body 310 so as to be opened and closed in up and down directions, and operated such that a lower end thereof is installed at the coping 20 or the installed girder 100 when being closed. Accordingly, when the vehicle 400 for carrying a girder is introduced into the crane 300 for pulling up a girder, the supplementary supporter 340 is opened (refer to FIGS. 11 and 12). On the contrary, just before the girder 100 a to be installed is pulled up, the supplementary supporter 340 is closed (refer to FIGS. 18 and 19).

Under this configuration, when the vehicle 400 for carrying a girder is introduced into the crane 300 for pulling up a girder, the supplementary supporter 340 may be closed. Also, when the vehicle 400 for carrying a girder is drawn out after the girder 100 a to be installed is pulled up, the supplementary supporter 340 and the vehicle 400 for carrying a girder may interfere with each other.

To solve the problem, the supporting portion 420 of the girder 100 include one pair of wing portions 421 a and 421 b for upward supporting the girder 100; and a wing portion opening/closing device 422 for inward closing the one pair of wing portions 421 a and 421 b, so as to prevent interference between the one pair of wing portions 421 a and 421 b and the supplementary supporter 340, at the time when the vehicle 400 for carrying a girder is backward moved after the supplementary supporter 340 is closed (refer to FIGS. 22 to 24).

Hereinafter, a preferred embodiment of the girder 100 will be explained with respect to the construction method for a girder in a bridge according to the present invention.

Any type of the girder 100 may be used as long as it can be pulled up by the crane 300 for pulling up a girder, and can be moved by the vehicle 400 for carrying a girder.

Here, the crane 300 for pulling up a girder can be more easily moved, by a guide groove 110 formed on an upper surface of the girder 100, to upper sides of the second front coping 21 a and the front coping 21, by guide of the first and second temporary girders 200 a and 200 b installed at the upper sides of the second front coping 21 a and the front coping 21. By the guide groove 110, the rear left supporter 323 or the rear right supporter 324 of the crane 300 for pulling up a girder is guided (refer to FIG. 43).

In order to prevent damage of the upper surface of the girder 100 while the crane 300 for pulling up a girder is moved, the crane 300 for pulling up a girder preferably has a plurality of supporting points to distribute a load thereof. To this end, while the crane 300 for pulling up a girder is moved, the supplementary supporter 340 is closed (the lower end of the supplementary supporter 340 comes in contact with the upper surface of the girder 100), and the motion of the crane 300 for pulling up a girder is guided by the guide groove 110 (refer to FIG. 43).

Hereinafter, FIGS. 11 to 43 will be explained according to the construction order for the girder according to the present invention.

Referring to FIG. 11, the first girder 100 a to be installed is installed on the supporting portion 420 of the girder 100 of the vehicle 400 for carrying a girder. Then, the vehicle 400 for carrying a girder is introduced into the pulling up space 301 of the crane 300 for pulling up a girder via an upper surface of the installed girder 100.

Referring to FIG. 12, the supplementary supporter 340 is driven so as to be upward opened, thereby preventing interference with the vehicle 400 for carrying a girder.

Referring to FIG. 13, the wheels 410 of the vehicle 400 for carrying a girder are introduced into the pulling up space 301 of the crane 300 for pulling up a girder via upper surfaces of the plurality of temporary girders 200.

Referring to FIG. 14, when the plurality of head portions 411 a, 412 a, 411 b and 412 b of the wheels 410 come in contact with the plurality of front supporters 321 and 322 and the plurality of temporary girder mounting and driving portions 360 of the crane 300 for pulling up a girder, the wheel connecting portion 413 is opened by the wheel connecting portion opening/closing means 440.

Referring to FIG. 15, under the state that the wheel connecting portion 413 is opened, the vehicle 400 for carrying a girder is forward moved to pass through the plurality of front supporters 321 and 322, and the plurality of temporary girder mounting and driving portions 360.

Referring to FIG. 16, in case that the wheel connecting portion 413 is mounted in plurality in back and forth directions, the front wheel connecting portion 413 is closed but the rear wheel connecting portion 413 is opened, while a part of the vehicle 400 for carrying a girder passes.

Referring to FIG. 17, as the above processes is repeatedly performed, the plurality of head portions 411 a, 412 a, 411 b and 412 b of the wheel 410 is moved via the plurality of front supporters 321 and 322 and the plurality of temporary girder mounting and driving portions 360, to a position where the girder 100 is to be pulled up.

Referring to FIG. 18, before the first girder 100 a to be installed is pulled up by the crane 300 for pulling up a girder, so as to distribute a load of the crane 300 for pulling up a girder onto an upper surface of the installed girder 100, the supplementary supporter 340 is closed.

Referring to FIG. 19, the crane base portion 341 comes in surface-contact with an upper surface of the installed girder 100 by the crane interval adjusting unit 342.

Referring to FIG. 20, the girder temporary mounting unit 331 is mounted on an upper surface of the first girder 100 a to be installed.

Referring to FIG. 21, the first girder 100 a is upward pulled by the up-down girder pulling device 330 by a certain height (high enough not to cause interference with the vehicle 400 for carrying a girder being drawn out).

Referring to FIG. 22, while the vehicle 400 for carrying a girder is drawn out, the one pair of wing portions 421 a and 421 b are inward closed so as to prevent interference between the supporting portions 420 of the girder and the supplementary supporter 340.

Referring to FIG. 23, when the wing portions 421 a and 421 b are opened (a lying posture), the two wheels 410 a and 410 b are supported. While the wing portions 421 a and 421 b are closed, the vehicle 400 for carrying a girder passes through an interference position with the supplementary supporter 340. Then, while the wing portions 421 a and 421 b are opened, the vehicle 400 for carrying a girder is drawn out.

Referring to FIG. 24, in case that the wing portions 421 a and 421 b are formed in plurality in back and forth directions, the vehicle 400 for carrying a girder is drawn out by repeatedly opening and closing the wing portions 421 a and 421 b, sequentially.

Referring to FIG. 25, the process for drawing out the vehicle 400 for carrying a girder is continuously performed until the wheel 410 of the vehicle 400 for carrying a girder is completely separated from the temporary girder 200 thus to reach an upper surface of the installed girder 100.

Referring to FIG. 26, the vehicle 400 for carrying a girder that has been completely drawn out is moved to a girder providing (or manufacturing) position so as to mount the second girder 100 b to be installed thereon.

Referring to FIG. 27, the first temporary girder 200 a is mounted at the temporary girder temporary mounting unit 351 of the temporary girder moving device 350 so as to be forward moved by the back-forth temporary girder moving device 352 of the crane 300 for pulling up a girder.

Referring to FIG. 28, the temporary girder base portion 220 is separated from the rear coping 22 by the temporary girder interval adjusting portion 221.

Referring to FIG. 29, the temporary girder moving base portion 230 is temporarily coupled to the first temporary girder 200 a by the moving base portion temporary coupling device 232.

Referring to FIGS. 30, 31 and 32, the first temporary girder 200 a mounted at the up-down temporary girder moving device 350 is forward moved by the back-forth temporary girder moving device 352.

Referring to FIG. 33, the temporary girder moving base portion 230 is forward moved by the moving base portion driving device 231.

Referring to FIG. 34, the temporary girder moving base portion 230 is mounted on an upper surface of the second front coping 21 a.

Referring to FIG. 35, the moving base portion temporary coupling device 232 is released such that the temporary girder moving base portion 230 serves as a supporting point to forward move the first temporary girder 200 a.

Referring to FIG. 36, after the first temporary girder 200 a mounted at the up-down temporary girder moving device 350 is forward moved by the back-forth temporary girder moving device 352, the first temporary girder 200 a is separated from the temporary girder temporary mounting unit 351 of the up-down temporary girder moving device 350.

Referring to FIG. 37, the first temporary girder 200 a is forward moved by the temporary girder mounting and driving portion 360, so that a rear end thereof is moved to an upper side of the front coping 21. Then, the temporary girder base portion 220 is mounted on an upper surface of the front coping 21 by the temporary girder interval adjusting portion 221.

Referring to FIG. 38, the up-down temporary girder moving device 350 is backward moved by the back-forth temporary girder moving device 352. The up-down temporary girder moving device 350 is moved to the right direction by the right-left temporary girder moving device 353, thereby preparing a subsequent forward motion of the second temporary girder 200 b.

Referring to FIG. 39, the first girder 100 a pulled up by the up-down girder pulling device 330 by the right-left girder moving device 332, is moved to the left direction thus to be mounted at upper sides of the front coping 21 and the rear coping 22.

Referring to FIG. 40, the girder temporary mounting unit 331 of the up-down girder pulling device 330 is separated from an upper surface of the first girder 100 a. The up-down girder pulling device 330 is moved to a central part by the right-left girder moving device 332, thereby preparing to pull up the second girder 100 b.

Referring to FIG. 41, the second girder 100 b is mounted on the vehicle 400 for carrying a girder, and the vehicle 400 for carrying a girder having the second girder 100 b thereon is introduced into the pulling up space of the crane 300 for pulling up a girder. Here, the supplementary supporter 340 is upward opened.

Referring to FIG. 42, the process for carrying the second girder 100 b is the same as the process for carrying the first girder 100 a, except that the vehicle 400 for carrying a girder moves at upper sides of the installed first girder 100 a and the second temporary girder 200 b. As the above processes are repeated, the second girder 100 b is mounted at upper sides of the front coping 21 and the rear coping 22.

Referring to FIG. 43, the crane 300 for pulling up a girder is moved to upper sides of the second front coping 21 a and the front coping 21 by guide of the first and second temporary girders 200 a and 200 b. The supplementary supporter 340 is downward closed. Also, rear supporters 323 and 324 of the crane 300 for pulling up a girder, and a lower end of the supplementary supporter 340 are guided by the guide groove 110 formed on upper surfaces of the first and second girders 100 a and 100 b.

As aforementioned, the construction method for a girder in a bridge according to the present invention can be applied even to a general roadway bridge, by a pre-cast method capable of implementing a high quality, a shortened construction duration, a reduced construction cost, etc.

Furthermore, the load of the crane 300 for pulling up a girder is uniformly distributed, thereby having structural stability.

The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.

As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims. 

1. A construction method for a girder in a bridge which a plurality of piers are installed in an interval in a longitudinal direction of the bridge, a plurality of copings are installed on the piers, and a plurality of girders respectively installed between the piers are installed on the copings, the method comprising the steps of: installing at least one temporary girder on a front coping of the copings and a rear coping adjacent to the rear coping of the copings; installing a crane for pulling up a girder having a girder pulling up space therein guided by the temporary girder; providing with a girder by a pre-cast method so as to install a girder on the front coping and the rear coping; providing with a vehicle for carrying a girder, the vehicle being constituted so that load of a girder to the piers carried by the vehicle is distributed to the piers through the upper surface of the girders installed in advance; introducing the vehicle carrying a first girder moving along a guide of the temporary girder to a girder pulling up space of the crane; pulling up the first girder by the crane; drawing out the vehicle backward from the girder pulling up space; moving a first temporary girder of the temporary girders from a position where the first girder is to be installed to a front of the front coping of the one of the copings and installing the first temporary girder on a next front coping installed in a next front of the front coping and the front coping; and settling the first girder on the front coping and the rear coping by the crane.
 2. The construction method for a girder in a bridge of claim 1, further comprising: the steps of introducing a vehicle moving by being guided by the temporary girder and the first girder and moving a second girder of the girders which is secondly installed for carrying a second girder to a girder pulling up space of the crane; pulling up the second girder by the crane; drawing out the vehicle backward from the girder pulling up space; moving a second temporary girder of the temporary girders from a position where the second girder is to be installed to a front of the front coping of the one of the copings and installing the second temporary girder on a next front coping installed in a next front of the front coping and the front coping; and settling the second girder on the front coping and the rear coping by the crane.
 3. The construction method for a girder in a bridge of claim 2, further comprising the step of: moving the crane guided by a guide of the first and the second temporary girders, after the step of settling the second girder.
 4. The construction method for a girder in a bridge of claim 1, wherein the piers are provided with in an interval in a width direction of the bridge.
 5. The crane for the construction method of claim 2, the crane comprising a crane body and a plurality of supporters vertically installed at a lower side of the crane body, the supporters supporting the crane body, wherein the supporters comprise: a front left supporter and a front right supporter installed at the front coping; and a rear left supporter and a rear right supporter installed at the girder installed in advance.
 6. The crane of claim 5, further comprising: an up-down girder pulling device installed at the crane body, the up-down girder pulling device having a girder temporary mounting unit for pulling up a girder, in order to pull up or be settled to an upper side of a girder; and a right-left girder moving device for moving the up-down girder pulling device in right and left directions.
 7. The crane of claim 5, further comprising a supplementary supporter installed at the lower side of the crane body so as to be opened and closed in up and down directions, and operated such that a lower end thereof is installed at the coping or the girder installed in advance when being closed, for resisting a load of the pulled-up girder together with the plurality of supporters when the girder is pulled up by the up-down girder pulling device.
 8. The crane of claim 7, wherein a crane base portion supported by being contacted with an upper surface of the coping or the girder installed in advance and a crane interval adjusting unit for adjusting an interval between the lower end of the supplementary supporter and the crane base portion are provided with at the end of the supplementary supporter.
 9. The crane for pulling up a girder of claim 7, wherein the supplementary supporter is installed between the rear left supporter and the rear right supporter.
 10. The crane of claim 5, further comprising: an up-down temporary girder pulling device installed at the crane body, the up-down temporary girder pulling device having a temporary girder temporary mounting unit for pulling up a temporary girder in order to pull up or be settled to an upper side of a temporary girder; and a back-forth temporary girder moving device for moving the up-down temporary girder pulling device in back and forth directions.
 11. The crane of claim 10, further comprising a right-left temporary girder moving device for moving the up-down temporary girder pulling device in right and left directions.
 12. The crane of claim 5, further comprising: a temporary girder supporting portion vertically installed at a lower side of the crane body; and a temporary girder mounting and driving unit installed at a lower end of the temporary girder supporting portion and mounted at the temporary girder, for allowing a relative operation between the temporary girder and the lower end of the temporary girder supporting portion.
 13. The crane of claim 12, the temporary girder mounting and driving unit comprises: a temporary girder mounting portion extended by being divided into two parts from the lower end of the temporary girder supporting portion; and a side guide roller portion installed at a lower end of the temporary girder mounting unit, and moving along side guide grooves formed at both sides of the temporary girder.
 14. The crane of claim 12, wherein the crane body comprises a crane extended body portion extending towards a front of the front coping, and the temporary girder supporting portion and the temporary girder mounting and driving unit are respectively installed at sides of the front left supporter and the front right supporter, and at a front lower side of the crane extended body portion, respectively.
 15. The crane of claim 13, wherein a pair of the temporary girder supporting portions are installed at right and left sides of the front left supporter, and a pair of the temporary girder mounting and driving units are installed at right and left sides of the front right supporter.
 16. The temporary girder for the construction method of claim 13, comprising side guide grooves formed at both sides for guiding the crane.
 17. A temporary girder used to the construction method for a girder in a bridge together with the crane for pulling up a girder of claim 15, wherein the temporary girder is installed at right and left sides of the front left supporter in one pair, and is installed at right and left sides of the front right supporter in one pair.
 18. A temporary girder used to the construction method for a girder in a bridge of claim 2, comprising: a temporary girder base portion installed at a lower side thereof, and supported by contacting an upper surface of the coping; and a temporary girder interval adjusting portion for adjusting an interval between a lower surface of the temporary girder and the temporary girder base portion.
 19. A temporary girder used to the construction method for a girder in a bridge of claim 2, comprising: a temporary girder moving base portion installed on a lower surface of the temporary girder so as to be movable back and forth, and installed on an upper surface of the front coping or the next front coping, for preventing downward deformation of the temporary girder being moved towards a front side of the front coping; and a moving base portion driving device for applying a driving force to the temporary girder moving base portion in back and forth directions.
 20. A temporary girder used to the construction method for a girder in a bridge together with the crane for pulling up a girder of claim 10, comprising: a temporary girder moving base portion installed on a lower surface of the temporary girder so as to be movable back and forth, and installed on an upper surface of the front coping or the next front coping, for preventing downward deformation of the temporary girder being moved towards a front side of the front coping; a moving base portion driving device for applying a driving force to the temporary girder moving base portion in back and forth directions; and a moving base portion temporary coupling device for temporarily coupling the moving base portion to the temporary girder when the temporary girder is forward moved by the crane for pulling up a girder.
 21. A vehicle for carrying a girder, used to the construction method for a girder in a bridge of claim 2, comprising: a left wheel operated by a guide of the first temporary girder or the first girder; a right wheel operated by a guide of the second temporary girder or the second girder; and a central body portion having a supporting portion for the girder at a central part thereof, for connecting the left and the right wheels with each other.
 22. A vehicle for carrying a girder, used to the construction method for a girder in a bridge together with the crane for pulling up a girder of claim 15, comprising: a left wheel operated by a guide of the first temporary girder or the first girder; a right wheel operated by a guide of the second temporary girder or the second girder; and a central body portion having a supporting portion for the girder at a central part thereof, for connecting the left and right wheels with each other, wherein one pair of right and left head portions are formed at a front end of the left wheel by being divided into two so as to be driven via one pair of temporary girder mounting and driving portions installed at right and left sides of the front left supporter, wherein one pair of right and left head portions are formed at a front end of the right wheel by being divided into two so as to be driven via the one pair of temporary girder mounting and driving portions installed at right and left sides of the front right supporter.
 23. The vehicle for carrying a girder of claim 22, further comprising: a wheel connecting portion installed at each front end of the one pair of head portions of the left wheel and the one pair of head portions of the right wheel, for connecting the respective one pair of head portions of the left and right wheels with each other; and wheel connecting portion opening/closing means for opening and closing the wheel connecting portion, so as to prevent interference between the wheel connecting portion and the temporary girder mounting and driving portion while the wheel is driven.
 24. The vehicle for carrying a girder of claim 23, wherein the wheel connecting portion opening/closing means comprises: a hinge portion installed at one end of the wheel connecting portion; and a wheel connecting portion opening/closing device mounted at the hinge portion, for opening and closing another end of the wheel connecting portion.
 25. A vehicle for carrying a girder, used to the construction method for a girder in a bridge together with the crane for pulling up a girder of claim 7, comprising: a left wheel operated by a guide of the first temporary girder or the first girder; a right wheel operated by a guide of the second temporary girder or the second girder; and a central body portion having a supporting portion for the girder at a central part thereof, for connecting the left and right wheels with each other, wherein the supporting portion of the girder comprises: one pair of wing portions for upward supporting the girder; and a wing portion opening/closing device for inward closing the one pair of wing portions, so as to prevent interference between the one pair of wing portions and the supplementary supporter, at the time when the vehicle for carrying a girder is backward moved after the supplementary supporter is closed.
 26. A girder used to the construction method for a girder in a bridge together with the crane for pulling up a girder of claim 5, comprising: a guide groove formed on an upper surface of the girder, for guiding a lower end of the rear left supporter or the rear right supporter of the crane for pulling up a girder, by a guide of the first and the second temporary girders installed at upper sides of the second front coping and the front coping, at the time when the crane for pulling up a girder is moved to be installed at upper sides of the next front coping and the front coping.
 27. A girder used to the construction method for a girder in a bridge together with the crane for pulling up a girder of claim 8, comprising: a guide groove formed on an upper surface thereof, for guiding at least one lower end of the rear left supporter, the rear right supporter, or the supplementary supporter of the crane for pulling up a girder, by a guide of the first and the second temporary girders installed at upper sides of the next front coping and the front coping, at the time when the crane for pulling up a girder is moved to be installed at upper sides of the next front coping and the front coping. 